The present invention relates to chair apparatus and, in particular, to an adjustable, non-rebound impact absorption type chair for use in supporting a crew member of an off-shore type powerboat.
In the sport of off-shore boat racing, large, heavy boats having sufficient power to propel the boat at speeds in excess of 80 to 90 miles per hour are used. Because these boats are raced in the ocean where there are generally large swells or waves, the speed of the boats causes them to leave the water and fly through the air (sometimes being airborne for up to 10 seconds) from wave to wave or swell to swell to obtain maximum speeds. As the boat hull contacts each wave, a tremendous shock is generated because of the three-to-four ton weight of the boat. The crew of such boats (generally a three man crew) must absorb these shocks and still continue to function. Since a race typically lasts several hours, it is necessary that this continual shock due to the periodic impact of the hull against the waves be absorbed by the crew members for sustained periods of time.
The chair or seat assemblies used in off-shore racing boats at the present time consist merely of a wrap-around half cylinder type assembly which is vinyl covered polyurethane foam on a wood base member. Such a seat is provided for each crew member with the crew member standing in the region encircled by the half cylinder type seat. Such an apparatus is not truly a seat since the crew member does not sit. Rather, the device simply keeps the crew member from being violently thrown left to right and from being propelled backwardly when each shock due to the boat impacting a wave occurs. Furthermore, present seats utilized in such off-shore racing boats do not provide any adjustments to take into account the varying sizes of crew members nor do they attempt to provide any vertical cushioning or absorption of the shock. Thus, the shock is not absorbed by the seat at all. Rather, each crew member uses his knees to absorb as much of the shock as possible or alternatively, to merely bounce around. Furthermore, the forces created by the shock of impact on each wave when these off-shore racing boats are travelling at racing speeds often make it impossible for the knees and legs to fully absorb the shock.
The present invention is directed to a chair assembly which may be used by individual crew members in off-shore powerboats and in particular in off-shore racing boats. The seat of the present invention is provided with adjustable side members to permit the size of the interior, occupant support region, to be varied in size to fit the width of a particular crew member. In addition, the entire seat assembly is vertically adjustable along an upstanding support member to enable the seat to be adjusted to account for the height of the individual crew member.
In use in a racing situation, a crew member will lean or otherwise be partially supported by positioning of his buttocks against a posterior support portion of the seat. The crew member then stands with his knees partially bent and his buttocks supported by the seat or chair assembly of the present invention.
In order that the present invention provides some impact absorption without rebound of the crew member, the interior portion of the chair apparatus in which the crew member positions himself is provided with a non-rebound impact absorption pad, which comprises a plurality of layers of visco-elastic foam, such as the temper foam sold by Edmont-Wilson Company, where each layer has a different degree of firmness.
Various types of adjustable seats and cushion apparatus have been previously known. For example, in U.S. Pat. No. 4,031,579, filed Dec. 19, 1975, to Larned, a cushion is disclosed for utilization in an aircraft seat by a crew member. The cushion is laminated and includes a foam shock absorbent layer and a layer of visco-elastic foam with an outer layer designed of high porosity material to provide ventilation. However, this reference does not disclose multiple layers of visco-elastic foam as is disclosed in the present invention, wherein each layer has a degree of firmness different from that of adjoining layers. Furthermore, the Larned seat is primarily for supporting the entire weight of an occupant while the present invention is for the primary purpose of assisting in absorbing impact shocks.
In U.S. Pat. No. 3,165,355 to Hitchcock, filed July 30, 1963, an aerospace seat for use in high acceleration environments is disclosed as including a shell to which a plurality of foam layers are attached. More specifically, that patent discloses that the layer closest to the shell has the highest bulk modulus and hence the least compressibility while the layer farthest from the shell has the lowest elastic bulk modulus and, thus, the most compressibility. The middle layer then has a bulk modulus intermediate therebetween.
In U.S. Pat. No. 2,195,428 to Searing, a seat is disclosed with a hinged forward seat section which may be dropped down if desired. However, this hinged forward seat section is for the purpose of a leg rest while, in the present invention, the hinged forward seat section actually provides for seating space rather than a leg rest. This is because of the relatively narrow seating space required by the crew person in a racing environment where the seat is used not as a complete support but only as a partial support for the crew member.
Finally, in U.S. Pat. No. 3,420,475 to Castillo, et al, filed Sept. 6, 1966, a support for a seat in an aircraft provides for both vertical adjustment of the seat and impact absorption. However, this seat again is for the purpose of absorbing the entire impact and completely supports the human occupant when in use. In addition, the side members of the seat are not adjustable to provide for varying sizes of seat occupants.